Although there won't be an enormous amount of choices among motherboards supporting both the ATI RD580 chip and Socket 939 since it seems like quite a few companies are skipping the Socket939 and waiting for the AM2 to be released.
Actually, I had read that article by Anandtech, but wasn't quite clear of the difference between the A8R and the A8R32, except where overclocking was concerned. I haven't had much success in that area and, so, wasn't planning on overclocking anyway.
Sounds like the X1900's are the way to go for now. I had thought about waiting; however, if you wait for one thing, you end up waiting forever. And, with my current PC (which hasn't been upgraded in years), I think I've waited long enough and am justified in spending what I will with this.